Gelatinized propellant-explosive and process of preparing same



UNITED. STATES PATENT OFFICE.

FREDEEIC LEWIS NATHAN AND WILLIAM RINTOUL, OF STEVENSTON, AND FRANK BAKER, DECEASED, LATE OF STEVENSTON, SCOTLAND, BY HENRY BAKER, OF ETON, WINDSOR, ENGLAND, ADMINISTRATOR OF SAID FRANK BAKER, ASSIGNORS TO NOBELS EXPLOSIVES COMPANY, LIMITED, OF GLASGOW, SCOTLAND.

GELATINIZED PROPELLANT-EXPLOSIVE AND PROCESS OF PREPARING SAME.

No Drawing.

To all whom it may concern:

Be it known that Colonel Sir Fanonnrc Lnwrs NATHAN and WILLIAM RINTOUL, both subjects of the King of Great Britain and Ireland, and residing at Ardeer, Stevenston, Ayrshire, Scotland, and FRANK BAKER, deceased, late of Ardeer, Stevenston, Ayrshire, Scotland, invented a certain new and useful Gelatinized Propellant-Explosive and Process of Preparing Same, of which the following is a specification.

Present day smokeless powders are generally prepared by gelatinizing nitrocellulose, either when used alone or with nitroglycerin, by a volatile solvent but this entails certain disadvantages, the drying process for removing the solvent being engthy and, what is worse, besides tending owing to the heat ing to affect the stability, is incomplete, so

that during storage an after-drying and slow production of irregularities in the material can occur.

In the course of investigations upon the stabilizin of nitric-ester-containing explosives we ound that certain esters of substituted carbaminic acids containing one or more aromatic radicals-see United States application No. 771,623Patent No. 1090644, granted March 17, 1914; are particularly adapted for use for stabilization but we have further found that among these bodies some are also effective gelatinizers for mixturesof nitroglycerin and nitrocelluloses.

According to the present invention therefore we utilize one or more such substances to produce a gelatinized propellant explosive from these nitric esters, the gelatinizer remaining in the final product and acting as stabilizer.

The following is a list of some of the substances referred to which possess this double property, namely:-

Y Phenyl urethane "C H, O,N Ethyl phenyl urethane C,,H,,O,N Diphenyl urethane -G,,H O N Ortho-tolyl urethane -C ,,H,' O,,N Ethyl ortho-tolyl urethane C, H -,O N Phenyl ester of ethyl phenyl carbaminie acid ,H O N Phenyl ester of diethyl carbaminic acid H O N Moreover, homologues and certain deriva- Specification of Letters Patent.

Patented Oct. 1, 1918.,

Application filed February 26, 1914. Serial No. 821,886.

tives of these substances possess like properties. Thus the substitution of a methyl for an ethyl group in ethyl phenyl urethane or of a hydrogen atom in a phenyl roup by the grouping O.CH or ---O.(], 5 in as far as possible from Water by pressing and rolling between rollers heated to from 40 to 50 C. after which it is a ain rolledat a temperature of from 50 to $0" G. and a gelatinized sheet of the desired thickness obtained which is either cut into strips or flakes or extruded from a press, the pressure required in the latter (usually some hundreds of atmospheres) falling with rise in the temperature adopted WhlCh may conveniently be between 50% and 70 C.

The bodies considered vary in their gelatinizing effect and the solution of the material to be used in any particular casealso depends largel upon the nature of the nitrocellulose to he treated, a powerful gelat inizer being more suitable for gun cotto' or insoluble nitrocellulose than weak gelatix poorer gelatinizing power of the one being compensated by the better gelatinizing power of the former and vice versa as regards their stabilizing effects. 1

The amount of the gelatinizing and stabilizing agent or agents used will vary, but

generally be between 5% and 12% of the whole mixture.

The physical properties of the. agent or agents used will afl'ect the above method of introduction into the mixture for while liquid bodies suchas ethyl tolyl urethane are easily dissolved in the nitroglycerin, solids require to be finely ground and thorohghly agitated with the nitroglycerin or to be melted, if of low fusing point, and so added to the nitroglycerin. By admixture the melting point may be reduced, a mixture of some of these bodies which separately are solid, being more or less liquid at temperatures but little above normal. Where the substance orsubstances used is or are soluble in water and the wet incorporation method is used, the suspension should be efi'ected in a solution of the substance or substances of such strength that, havin regard to the mixture used the right nal composition results.

Having now described our invention, what we claim as new and desire to secure by Letters Patent is 1. The rocess for producing a gelatinized and stabi ized propellant explosive which comprises mixing together nitroglycerin, nitrocellulose and an aromatic-radical-containing substituted carbamic acid ester capable both of gelatinizing nitrocellulose and of stabilizing nitric esters, and a second body also possessing both these properties, one of the latter two bodies possessing the first mentioned property to a smaller extent and the second mentioned property to a'larger extent than the second mentioned body, and

then elatinizing the mixture.

2. he process for producing a gelatinized and stabilized propellant explosive which comprises mixing together nitroglycerin, nitrocellulose and an aromatic-radical-containing urethane capable both of gelatinizing nitrocellulose and of stabilizing nitric esters, and a second body also possessing both these properties, one of these latter two bodies possessing the first mentioned property to a smaller extent and the second mentioned property to a larger extent thanthe second mentioned body, and then urethane capable both of gelatinizing nitrocellulose and of stabilizing nitric esters, and another stabilizing and gelatinizing compound also possessing'both these properties, one of these two stabilizing and gelatmizing compounds, possessing the first mentioned property to a smaller extent and the second mentioned property to a larger extent than the other such compound.

5. A gelatinized propellant explosive containing nitroglycerin, nitrocellulose and a phenyl ester of ethyl phenyl carbamic acid.

6. A gelatinized propellant explosive containing about 40 parts of nitroglycerin, about 50 parts of nitrocellulose, and a small amount of a phenyl ester of ethyl phenyl carbamic acid.

In testimony whereof we have signed our names to this specification in the presence of subscribing witnesses.

FREDERIC LEWIS NATHAN. WILLIAM RINTOUL. HENRY BAKER, Aehnim'stmtor of the estate of F rank Baker,

deceased.

Witnesses:

N. B. MILNE, ALEx. FORBES, BERTRAM H. MATTHEWS, P. A; OUTHWAITE. 

